Nutrient Dynamics in Fodder Based Teak Agroforestry System

Abstract

The study aimed to assess the influence of varying teak planting densities and different perennial fodder crops on the physical and chemical properties of soil. The field experiment was carried out from June 2021 to May 2022 at the AICRP on Agroforestry Unit, ZARS, GKVK, UAS, Bangalore, Karnataka. The experiment followed a split plot design with three teak planting densities (12 m × 3 m, 10 m × 3 m and 8 m × 3 m) assigned to the main plots and five perennial fodder crops (Guinea grass, CO-3, CO-5, Super Napier and BNH-10) were allocated to the subplots  in three replications. Soil samples were collected at 0–20 cm depth before fodder planting and after the harvest of the fodders to determine changes in texture, bulk density, porosity, organic carbon, pH, EC and available N, P₂O₅, and K₂O. Results showed a consistent improvement in bulk density (1.43 to 1.36 g cm⁻³), porosity (46.24% to 47.56%) and organic carbon (0.45% to 0.56%) with increased teak density, indicating better soil structure and carbon input. Available phosphorus significantly increased from 17.32 to 19.44 kg ha⁻¹ under closer spacing (p < 0.05), while nitrogen and potassium levels were also observed in positive trend. Fodder crops showed slight variation but found to be non-significant; sole fodder plots generally underperformed in all soil parameters. Interaction effects were statistically non-significant, though S3F3 (8 m × 3 m + CO-5) exhibited superior values in several indicators. The incorporation of teak with high-yielding perennial fodder crops had a beneficial impact on soil health, with closer tree spacing resulting in greater improvements. These findings support the viability of teak-based agroforestry systems for sustainable nutrient cycling and long-term land productivity in tropical agroecosystems.